Twelve is the magic number in fitness expert Denise Austin's diverse collection of five 12-minute workouts: "Cardio-Athletic," "Cardio Kickbox," "Lower Body Sculpt," "Upper Body Sculpt" and "Yoga Stretch." Each regimen presents a dozen one-minute exercises. Punch, kick, row, curl and jump your way to fitness in just 12 minutes a day. Austin has been a member of the President's Council on Physical Fitness and Sports since 2002.